<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <input v-model="val" type="text">
        <button @click="addItem">提交</button>

        <h2>正在进行 --- {{len}} </h2>
        <ul>
            <li v-for="(item,index) in arr" v-show="!item.checked">
                <input type="checkbox" v-model="item.checked">
                {{item.val}}
                <button @click="arr.splice(index,1)">删除</button>
            </li>
        </ul>


        <h2>已经完成 --- {{arr.length - len}} </h2>
        <ul>
            <li v-for="(item,index) in arr" v-show="item.checked">
                <input type="checkbox" v-model="item.checked">
                {{item.val}}
                <button @click="arr.splice(index,1)">删除</button>
            </li>
        </ul>


    </div>
    

    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
        new Vue({
            el:"#app",
            data:{
                val:"",
                arr:[],

            },
            methods: {
                addItem(){
                    this.arr.push({
                        val:this.val,
                        checked:false
                    })
                    this.val = ''
                }
            },
            computed:{
                len(){
                    return this.arr.filter((item)=>{
                        return item.checked === false
                    }).length
                }
            }
        })

    </script>
</body>
</html>